In his first-ever interview, the sole Australian survivor of the Waco siege has revealed to 60 Minutes what really took place during the 51-day stand-off, and why he believes crazed cult leader David Koresh will one day return to Earth as the son of God.

Parents sue over US teen's suicide

The family of a 15-year-old US girl who killed herself after she was sexually assaulted while drunk are suing three teenage boys accused of the attack and sharing a photo of it at their school.

In the latest such case, Audrie Pott committed suicide last September eight days after the alleged attack in which she was assaulted by three male schoolfriends after going to sleep at a party.

They had taken a photograph of the alleged assault, which was shared among friends at Saratoga High School, a lawyer for the family said at a press conference with her mother Sheila.

"After consuming alcohol .. she went to a bed to go to sleep, hoping to wake up the next day and go to school and start the school year. Instead she woke up to an absolute nightmare," said lawyer Robert Allard.

"The sexual assault was one thing ..and then to be publicly humiliated and disgraced in front of the whole school student body, that was to much for this young girl to take," he added, announcing a wrongful death civil lawsuit.

He added: "We intend to prove ... that their action not only for the sexual assault, but .. the despicable horrific, traumatic, defaming and savage actions they did in the next seven days, broke her.

"She couldn't handle it. And she did the worst thing a parent could ever imagine ... she ended her life."